Surprising trend in galaxy evolution (w/ Video)

October 19, 2012
by Francis Reddy

This plot shows the fractions of settled disk galaxies in four time spans, each about 3 billion years long. There is a steady shift toward higher percentages of settled galaxies closer to the present time. At any given time, the most massive galaxies are the most settled. More distant and less massive galaxies on average exhibit more disorganized internal motions, with gas moving in multiple directions, and slower rotation speeds. Credit: NASA/Goddard Space Flight Center

(Phys.org)—A comprehensive study of hundreds of galaxies observed by the Keck telescopes in Hawaii and NASA's Hubble Space Telescope has revealed an unexpected pattern of change that extends back 8 billion years, or more than half the age of the universe.

"Astronomers thought disk galaxies in the nearby universe had settled into their present form by about 8 billion years ago, with little additional development since," said Susan Kassin, an astronomer at NASA's Goddard Space Flight Center in Greenbelt, Md., and the study's lead researcher. "The trend we've observed instead shows the opposite, that galaxies were steadily changing over this time period."

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A study of 544 star-forming galaxies observed by the Keck and Hubble telescopes shows that disk galaxies like our own Milky Way unexpectedly reached their current state long after much of the universe's star formation had ceased. Over the past 8 billion years, the galaxies lose chaotic motions and spin faster as they develop into settled disk galaxies. Credit: NASA's Goddard Space Flight Center

Today, star-forming galaxies take the form of orderly disk-shaped systems, such as the Andromeda Galaxy or the Milky Way, where rotation dominates over other internal motions. The most distant blue galaxies in the study tend to be very different, exhibiting disorganized motions in multiple directions. There is a steady shift toward greater organization to the present time as the disorganized motions dissipate and rotation speeds increase. These galaxies are gradually settling into well-behaved disks.

Blue galaxies—their color indicates stars are forming within them—show less disorganized motions and ever-faster rotation speeds the closer they are observed to the present. This trend holds true for galaxies of all masses, but the most massive systems always show the highest level of organization.

Researchers say the distant blue galaxies they studied are gradually transforming into rotating disk galaxies like our own Milky Way.

"Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today," said co-author Benjamin Weiner, an astronomer at the University of Arizona in Tucson. "By neglecting them, these studies examined only those rare galaxies in the distant universe that are well-behaved and concluded that galaxies didn't change."

Rather than limit their sample to certain galaxy types, the researchers instead looked at all galaxies with emission lines bright enough to be used for determining internal motions. Emission lines are the discrete wavelengths of radiation characteristically emitted by the gas within a galaxy. They are revealed when a galaxy's light is separated into its component colors. These emission lines also carry information about the galaxy's internal motions and distance.

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Simulations such as this will help astronomers better understand the new findings in galaxy evolution. It tracks the development of a single disk galaxy from shortly after the Big Bang to the present day. Colors reveal old stars (red), young stars (white and bright blue) and the distribution of gas density (pale blue); the view is 300,000 light-years across. Credit: F. Governato and T. Quinn (Univ. of Washington), A. Brooks (Univ. of Wisconsin, Madison), and J. Wadsley (McMaster Univ.).

The team studied a sample of 544 blue galaxies from the Deep Extragalactic Evolutionary Probe 2 (DEEP2) Redshift Survey, a project that employs Hubble and the twin 10-meter telescopes at the W. M. Keck Observatory in Hawaii. Located between 2 billion and 8 billion light-years away, the galaxies have stellar masses ranging from about 0.3 percent to 100 percent of the mass of our home galaxy.

A paper describing these findings will be published Oct. 20 in The Astrophysical Journal.

The Milky Way galaxy must have gone through the same rough-and-tumble evolution as the galaxies in the DEEP2 sample, and gradually settled into its present state as the sun and solar system were being formed.

In the past 8 billion years, the number of mergers between galaxies large and small has decreased sharply. So has the overall rate of star formation and disruptions of supernova explosions associated with star formation. Scientists speculate these factors may play a role in creating the evolutionary trend they observe.

Now that astronomers see this pattern, they can adjust computer simulations of galaxy evolution until these models are able to replicate the observed trend. This will guide scientists to the physical processes most responsible for it.

The DEEP2 survey is led by Lick Observatory at the University of California at Santa Cruz in collaboration with the University of California at Berkeley, the University of Hawaii at Manoa, Johns Hopkins University in Baltimore, Md., the University of Chicago and the California Institute of Technology in Pasadena.

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64 comments

There's a problem with the graph. If you look, you'll notice it says that, ay about 4.6 billion years ago, about 4% of all "settled" galaxies were about .3% of the Milky Way's mass, about 25% of all "settled" galaxies were about 3% of the Milk Way's mass, about 56% were 11% of the Milky Way and about 84% were close to the Milk Way's mass. That adds up to 169%. If you add in the galaxies heaver than the Milk Way, will that bring the total of "settled" galaxies to 200%? This may cause this not to be printed, but, interesting, too, that this is happening at clkose to 5 billion light years distance, where the Permutter group developed the fraudulent assessment that the universe has "sped up".

Ive read articles here and elsewhere stating that our galaxy could be several times more or less massive than we think. Here is one for instancehttp://phys.org/n...gas.htmlSo doesnt that make studies like this look a bit silly ?

There's a problem with the graph. If you look, you'll notice it says that, ay about 4.6 billion years ago, about 4% of all "settled" galaxies were about .3% of the Milky Way's mass, about 25% of all "settled" galaxies were about 3% of the Milk Way's mass, about 56% were 11% of the Milky Way and about 84% were close to the Milk Way's mass. That adds up to 169%. If you add in the galaxies heaver than the Milk Way, will that bring the total of "settled" galaxies to 200%? This may cause this not to be printed, but, interesting, too, that this is happening at clkose to 5 billion light years distance, where the Permutter group developed the fraudulent assessment that the universe has "sped up".

No, it says that, at about 4.6 billion years ago, about 4% of the smallest galaxies (those of about .3% of the Milky Way's mass) were "settled". Each line represents a different set of galaxies. The percentages are independent of each other.

The changing function of everything in the universe is going on always. The present scenery was not similar with past and also will not resemble with the future, the present and past space-time energy absolute zero of absolute time. As per formula of evolution; going to the last border/boundary of everything of creation, it would be felt nothing except touch of nature power. In the finalization of matter there is nothing but energy or ray, so we can take the decision that "Everything of the present universe is the result of evolution of single energy of Power".

Ive read articles here and elsewhere stating that our galaxy could be several times more or less massive than we think. Here is one for instancehttp://phys.org/n...gas.htmlSo doesnt that make studies like this look a bit silly ?

Yep, this is not science, this is pseudo science full of conjecture.Doing simulations or math on something we cant even remotely measure is stupidity. Prime example of academic dogma.

Ive read articles here and elsewhere stating that our galaxy could be several times more or less massive than we think. Here is one for instancehttp://phys.org/n...gas.htmlSo doesn't that make studies like this look a bit silly ?

Not nearly as much as you might think. There are substantial reasons to believe that most if not all galaxies contain a lot of mass that we cannot see. However, its also true, that for the most part, the luminous part that we can see is a reasonable proxy for the overall mass.

Of course there are probably galaxies in which a large majority of the mass is luminous, and also those with a balance the other way. But by doing a statistical survey of enough galaxies, its a pretty reasonable assumption that most galaxies that are 10 times as luminous ( for example) are a lot more massive than ones than those that are much fainter, no matter what the balance of the unseen portion is.

In fact. drel's "explanation" of the graph is wrong. The vertical axis says "Percentage of Settle Galaxies". That means that each line is supposed to represent the percentage of all settle galaxies that fall into each category. drel is "interpreting" it in a patently illegitimate way simply to contradict me. And note that my correct interpretation receives only 1 star out of 5 while drel's invalid one receives 5. Another part of the pattern of character assassination PhysOrg facilitates. In fact, I usually get a "1" rating, by the craven, because they figure that, even if I get a genuine "5" next, that will knock the average down to "3". There is genuine viciousness acting on this site. In fact, no one should be allowed to place a rating unless they give their username. Requiring an explanation, too, likely will cut down significantly on the number of craven ratings.

"The trend we've observed instead shows the opposite, that galaxies were steadily changing over this time period."

In AWT the Universe is steady-state, but inherently random and the galaxies do behave like giant fluctuations of dense gas: they do condense from dark matter clouds (which are itself forming inside the gravitation shadow of another galaxies) and they do evaporate again into radiation (photons and neutrinos, which do condense somewhere else). The evidence of this behavior can be observed even with geometry of dark matter, which appear like the rosary string with prayerbeads distributed along it. This is because the dark matter is concentrated just along connection lines of another galaxies (where the gravitational shadow becomes most prominent) - so that most of galaxies is condensing right there.

Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today

This is what the data fishing is called. Of course, if you select only galaxies in certain stage of their evolution, then you cannot recognize, the do evolve at all. But I do suspect, not only the laziness of researchers, bit even the common belief in Big Bang theory participated in this bias ("..there is no actual reason to study the evolution of galaxies, when Big Bang theory says, they don't evolve already and when Big Bang model was confirmed so many times"...). The memo is, the scientists should learn the scientific method for whole their life, because no simple rule can be applied here: they can be fooled in each moment of research in some new unpredicted yet way.

The galaxies indeed cannot grow from completely nothing and the behaviour of Universe at largest scales is very ambiguous: a mixture of mutually dual mechanisms should be always considered here. A similar trend like at the case of planetary growth may be observed here. The large planets are formed with condensation of gas from protoplanetary disk, which is why they contain huge amount of hydrogen and lighter gases. The small planets are formed with gradual accretion of smaller pieces into existing metallic core, which keeps them degassed. I presume, the galaxies do grow similarly: these small ones are formed with gradual condensation of gas (which essentially corresponds the Big Bang model) - but the large ones are formed from large clouds of dark matter in a single moment, when this cloud collapse gravitationally into quasars or active galactic nuclei. They do their own tiny Big Bangs, so to say - which we just observe from the dual perspective

In fact. drel's "explanation" of the graph is wrong. The vertical axis says "Percentage of Settle Galaxies". That means that each line is supposed to represent the percentage of all settle galaxies that fall into each category. drel is "interpreting" it in a patently illegitimate way simply to contradict me.

Nope. I'll give you that the graph label could be more clear, but drel is clearly correct. Watch the video. Or read the article. Or use common sense. Your choice really.

Also, you can see who has ranked each comment; though you can't see who gave you each ranking. I'll explain mine for you. I rated drel a 5 because he was correct, on topic, and added information; and you a 1 because you were incorrect. I rated your second comment a 1 because it was delusional, paranoid, and incorrect. It made me wish I had rated your first comment a 2 or 3 because it was at least understandable and made you look like you were trying to be reasonable.

The growth curves presented above do correspond this scheme in essence: at the moment, when large galaxy is formed with condensation of gravastar, it doesn't grow anymore and its curve remains flat. The medium sized galaxies are using both mechanisms, whereas these small ones just grow faster and faster, because the accretion mechanism tends to be the faster, the heavier the galaxy already is.

But all these curves still appear biased, because they don't document any decay or evaporation of galaxies - they're all of positive slope only. Whereas we already know, that the Milky Way or Andromeda are surrounded with many ancient dwarf galaxies, which are stripped of their gas and as such much smaller than before. Many of them were swallowed already with larger galaxies. But where the negative slope of their galactic growth is? It's not documented with this study at all not because these galaxies don't exist - but because they were still ignored and excluded from the survey.

New and old ScienceA new and Progressive Science shows how Wavevolution, or the transformation from waves to atoms, is the connecting link that closes the circle of science to open new horizons never seen before.The bureaucracy of traditional science prevents the recognition of any event unless certain criteria are first met. The problem of this science is buried deep right in the compilation of these "laws" or criteria introduced by a few scientists in the name of all science and from their erroneous understanding of the relation between Space and Time. This antiquated system of rules also results in misleading theories.

The general implication seems to be that the "settling" of galaxy, essentially an ordering of sorts of planetary motions increases in speed with the size of the galaxy. They seem to be trying to depict collisions with matter as the only source of this ordering. But mutual gravitation can be another. The change in p[aths of the curves for various masses of galaxies occur at different times, which shouldn't be if every part of the universe had the same amount of random matter. Too, it seems unreasonable that loose matter should have become so scarce at about 6.5 billion years ago that large galaxies would "settle" more slowly. So gravity must be the cause. But "dark matter" is supposed to exert at least 10 times the gravity of visible matter. So why the difference in "settling"?

This is what most can't quite grasp...that indeed matter nucleates from nothing, if one defines that 'nothing' as something that simply cannot be detected in our universe. (Kinda sounds like that dark matter nonsense...) But this is different.

The nothing is simply too small...much smaller than the smallest detectable sub-atomic particle. But the reaction of these nothings among each other sometimes align to create a self-sustaining reaction among themselves that we call a sub-atomic particle. This is SubQuantum Kinectics. It is a prediction from General Systems Theory models. This new matter nucleation is what happens at an accelerated pace in the dense regions of the center of the galactic core stars.

There's a problem with the graph. If you look, you'll notice it says that, ay about 4.6 billion years ago, about 4% of all "settled" galaxies were about .3% of the Milky Way's mass, about 25% of all "settled" galaxies were about 3% of the Milk Way's mass, about 56% were 11% of the Milky Way and about 84% were close to the Milk Way's mass. That adds up to 169%. If you add in the galaxies heaver than the Milk Way, will that bring the total of "settled" galaxies to 200%?

Emphasis is on "settled", not the percentage. As drel pointed out the percentages are independent. If one was to say (for example) 82% of men were heterosexual and 76% of women were heterosexual, would you then add them up and say "158% of the population are straight, that doesn't make sense!"? No of course not.

The percentages are respective of the sizes, but the graph title is not incorrect. I guess they assumed readers would use a little of their own reason. Evidently they assumed too much of some.

This is what most can't quite grasp...that indeed matter nucleates from nothing, ..

You seem to be thinking of some empty space solution. Current models say the first stars condensed out of the slowly thinning hydrogen gas that filled the universe after the plasma that emitted the CMBR became neutral.

Look up "Jeans Instability" for the details of how that would happen, for example:

For those new to the site, there is no such thing as "AWT", it means "in the poster's opinion".

the Universe is steady-state, but inherently random ..

The growth curves presented above do correspond this scheme in essence: ... The medium sized galaxies are using both mechanisms, ...

No, if the universe were steady state, all the curves would be horizontal lines, the same value irrespective of time. The value would depend only on the mass.

But all these curves still appear biased, because they don't document any decay or evaporation of galaxies - they're all of positive slope only. ..

When galaxies collide, their motions are perturbed but they settle down to simpler patterns after that (until the next collision). As time goes on and the universe expands, collisions become less frequent and eventually all the curves will reach 100% as the Hubble flow becomes dominant hence there should be no negative slope. (They are not measuring growth at all.)

As stars pass close to each other, their paths within a galaxy will be changed, that would be the dominant mechanism for "settling".

The change in paths of the curves for various masses of galaxies occur at different times, which shouldn't be if every part of the universe had the same amount of random matter. .. So why the difference in "settling"?

The universe is expanding. At any given time, the density is roughly the same on large scales but that value is falling as a function of cosmic age. As the more uniform material falls into smaller bound regions due to Jeans Instability and galaxies and clusters are then virialised, the patterns become more stable.

Logically, if a large galaxy is hit by a dwarf, it isn't going to be perturbed much whereas the merger of Andromeda and the Milky Way will be significant. There are still many dwarfs around, larger collisions are becoming rarer.

Ive read articles here and elsewhere stating that our galaxy could be several times more or less massive than we think. Here is one for instancehttp://phys.org/n...gas.htmlSo doesnt that make studies like this look a bit silly ?

Yep, this is not science, this is pseudo science full of conjecture.Doing simulations or math on something we cant even remotely measure is stupidity. Prime example of academic dogma.

The mass is only used as a means of grouping the galaxies, the actual mass is irrelevant so using the luminosity is valid regardless of the mass-to-light ratio.

Your post is a prime example of the arrogance of someone who knows nothing thinking they are better placed to understand than those who have studied the subject.

We will be able to learn more about our universe once we get over the notion of a 'Big Bang'. The Big Bang theory has two major holes in its logic:a)it refutes the basic premise of physics: that energy can neither be created nor destroyed, it can only change form; and,b)it discredits the Black Hole theory in that, if a black hole's gravity is so intense that not even light, which is massless, can escape; then with everything we can percieve now was at one time in a single point, then it would have been the Mother of All Black Holes; and there would not have been enough energy to make it go 'Bang'.

Any time you have a paradox; you will find a false premise. It is time we ditched the vestigial Catholic Church concept that the Universe had a beginning, just because it says 'In the Beginning' in the bible.

it just means, that this opinion follows certain paradigm and it can be deduced from it in reproducible way and it brings testable predictions. You're not required to call it a theory, if you don't want to.

that indeed matter nucleates from nothing, if one defines that 'nothing' as something that simply cannot be detected in our universe

IMO the content of observable matter in our Universe is constant and defined with us, human observers: what condenses here is evaporated somewhere else. Analogously the entropy of the observable Universe remains constant.

The universe is expanding.

IMO the matter in Universe couldn't even condense if it would expand with observed size. After all, the Einstein's expansion paradox is one of the motivations of Multiverse concept.

With compare to it, the AWT model of space-time with water surface explains this paradox quite simply: for every observer or source of waves at the water surface the surface appears expanding (the water ripples collapse) - although nothing actually expands or moves here. And no Big bang, no multiverse is required for explanation of this behavior: it's the result of common scattering of waves inside of particle environment.

a)it refutes the basic premise of physics: that energy can neither be created nor destroyed, it can only change form; and,

The sum of all energy created in BB is zero, so that is not violated by BB theory at all.

ab)it discredits the Black Hole theory in that, if a black hole's gravity is so intense that not even light, which is massless, can escape; then with everything we can percieve now was at one time in a single point, then it would have been the Mother of All Black Holes; and there would not have been enough energy to make it go 'Bang'.

We are inside that singularity, we are part of that single starting point. We never had a chance to look at it from the outside. For us, there is no outside.

a)it refutes the basic premise of physics: that energy can neither be created nor destroyed, it can only change form; and,

Not necessarily. As someone already mentioned, if you take gravity as 'negative energy' then the whole thing comes out zero.http://en.wikiped...universe

Another thing to consider would be virtual particle pairs (of which we know through things like the Casimir effect). But which have a sumtotal energy of zero. So 'something from nothing' (and back again) is possible in energy matters.

b)it discredits the Black Hole theory in that, if a black hole's gravity is so intense that not even light, which is massless, can escape; then with everything we can percieve now was at one time in a single point

That goes only if space doesn't expand quite rapidly at the same time (as we think it did in the very early stages of the universe). If something falls inwards at maximum speed (i.e. speed of light) but space expands more rapidly (spatial expansion isn't limited by c) then you can get an overall decrease in density. Hence: no initial black hole.

Although I am sure many big black holes did form early on, just not to the point of having just one with everything in it.

if you take gravity as 'negative energy' then the whole thing comes out zero.

Unfortunatelly, this is just a dumb mathematical trick of some positivists, which has no experimental background. Even most of theories consider the energy of gravity as positive, as every else kind of energy. For example, in general relativity this energy causes the positive curvature of space and gravitational lensing in the same way, like any other source of energy. And the matter can be perceived as a dense system of space-time curvatures too. For example, when the large star evaporates, it releases its matter in the form of photons, which would contribute to gravitational mass of particles, which would absorb them. In famous experiment proving the E=mc2 equivalence the photons of gamma ray were absorbed with atom nuclei, which were subsequently weighted in atomic spectrophotometer. The excited nuclei were more heavier, it means they generated larger gravity field around itself, not smaller.

The consideration that the energy of gravity is negative would violate the equivalence principle and as such the relativity itself, on which the whole mass-energy equivalence is based. The Einstein's theory has no zero sign for energy of gravity field prepared. All forms of energy are causing the very same dilatation of time, like the gravity itself. In my theory it's because we are living in gradient driven reality: all gradients of energy contribute to it, no matter whether they're positive or negative. This equivalence is hardwired in Schroedinger equation of quantum mechanics too: only absolute value of Hamiltonian contributes to the amplitude of the probability wave - not the actual value of wave function.

a)it refutes the basic premise of physics: that energy can neither be created nor destroyed, it can only change form; and,b)it discredits the Black Hole theory in that, if a black hole's gravity is so intense that not even light, which is massless, can escape; then with everything we can percieve now was at one time in a single point, then it would have been the Mother of All Black Holes; and there would not have been enough energy to make it go 'Bang'.

Since we cannot see inside a black hole, we can't say that there is a singularity. Some other force may come in to play to stop it, for example, or space time may rip giving the in falling matter and energy someplace to go, which we would never see do to the time dilation effects. We simply don't know and anything else would be speculation. Therefore you can't rule out black holes or big bangs.

The existence of black holes and singularities follows from general relativity only. This theory predicts, all matter should collapse into singularity with no mercy. But we know already, the dense objects don't behave so - there are many repulsive forces which prohibit it, in particular the weak nuclear force. What's worse, the quantum mechanics cannot predict gravity and it has quite opposite predictions: in QM all objects are formed with quantum wave packets and they should expand into infinity. Again, we know that no observable object is behaving so: there are many another forces, which keep them together. So, despite the relevance of relativity at the scale of stars and despite the relevance of quantum mechanics at the scale of the atoms both theories are deeply lying both about observable objects, both contradict each other. From this perspective the existence of black holes is deeply speculative, their singularities the less.

What we can expect instead is, that the alleged black holes will be created with dense massive bodies, the physical surface of which would be quite close to so-called event horizon. They will be similar to dense stars and they would be quite radiative if the physical surface would be just a bit larger, than their event horizon - or quite dark, if it would be smaller. IMO the jets of rotating black holes is their own radiation, which penetrates the hole of their event horizon. It's because the physical surface of such object is less or more close to torus, so that their even horizon is not continuous. It's rather easy to understand, that our Universe is not formed with interior of black hole: not only it couldn't be homogeneous after then, but because it has inverse geometry to black hole: the black holes are described with Schwarzchild's metric, but the universe is described with FLRW metric.

The Big Bang theory has two major holes in its logic: a)it refutes the basic premise of physics: that energy can neither be created nor destroyed, it can only change form; and, b)it discredits the Black Hole theory

This article is about galaxy evolution, not cosmology as such. Your criticism of the previous "big bang" theory is entirely invalid since it doesn't concern itself with energy non-conservation or black holes.

And ironically, cosmologies of the type we observe are zero energy. Or physicists couldn't describe how tunneling can cause a universe to fluctuate into being from a previous universe. So there is no "creation" or "destruction" of energy involved.

Today's inflationary standard cosmology precedes the start of big bang, the first time that we can describe an expanding spacetime with matterenergy and a definite finite temperature, with an inflationary period. (Siegel.)

[cont] The generic physics of inflation is an eternal multiverse without any observable beginning. (Susskind.) Therefore it has another explicit prediction of no "creation" or "destruction" of energy.

This is old hat, already in the 70's they knew that the physics of cosmology obeyed thermodynamics. You are 40 years out of date.-----------

As for "AWT", of course there is no such theory. In as much as "aether" hypotheses makes a prediction, they were rejected by basic observations - a century ago (!). _Nothing_ can give that mummy life again.

And mostly it is an empty label-waving on science sites instead of on the crackpot sites it belongs to. To all appearances it makes a platform for its sole user to put incoherent claims together, which behavior is also mainstream crackpot.

Well, I guess suffering mundane somewhat structured crackpots (they have a label to repeat after all) is better than the insane stream-of-consciousness ones. :-/

"Previous studies removed galaxies that did not look like the well-ordered rotating disks now common in the universe today," said co-author Benjamin Weiner, an astronomer at the University of Arizona in Tucson. "By neglecting them, these studies examined only those rare galaxies in the distant universe that are well-behaved and concluded that galaxies didn't change."

Would be the first time allegedly "set in stone facts" were actually the result of human biases or misrepresentations.

I wonder how much else in astronomy and cosmology is warped by cherry-picked data sets? Never mind all other branches of sciences where less experimentation is possible.

Yeah, you can't produce an accurate computer simulation if you don't even use complete data.

I agree with an earlier comment; galaxies of all sizes should be studied, not just cherry picked sizes.

Another question this raises is why do galaxies allegedly arising through these semi-random collisions increase in their rate of spin?

Conservation of angular momentum easily explains this in the "simple" concept with the classic figure skater example.

BUT in the real universe colliding objects are coming from all directions, including objects with retrograde spins and retrograde orbits, which SHOULD serve to slow down the spin, so WHY the consistent pattern of increased rotation speed?

If two galaxies orbit a larger galaxy, and they have decaying orbits, one prograde, the other retrograde, then they should off-set one another's angular momentum, resulting in little change in the larger galaxy's final rotation speed (also causing a danger of a very large core collapse into SMBH).

So why does the data set favor collisions that have more prograde components than retrograde components, resulting in said chirality?

b)it discredits the Black Hole theory in that, if a black hole's gravity is so intense that not even light, which is massless, can escape; then with everything we can percieve now was at one time in a single point, then it would have been the Mother of All Black Holes; and there would not have been enough energy to make it go 'Bang'. ..

Others have corrected your point (a).

Point (b) is wrong because a black hole is a concentration of mass in a space of much lower density. Objects nearby fall into it because gravity accelerates them that way (in conventional coordinates).

The big bang is based on the Cosmological Principle that the mean density was the the same everywhere. Any object would then see as much matter on either side whereever it was in the universe, and only minimal net acceleration, it would not be a black hole.

Discard the Cosmological Principle and you would be right, hence the fact that the universe exists at all supports the premise of the Big Bang model.

if you take gravity as 'negative energy' then the whole thing comes out zero.

Unfortunatelly, this is just a dumb mathematical trick of some positivists, which has no experimental background.

If your lower an object tied with a rope on a genertor, you get energy out. The object's energy must therefore reduce. The Virial Theorem also shows that the potential energy of an orbiting body must be more negative than its positive kinetic energy.

most of theories consider the energy of gravity as positive, as every else kind of energy.

Nope, all current theories treat it as negative.

For example, in general relativity this energy causes the positive curvature of space and gravitational lensing in the same way ..

Nope, lensing is due to the positive energy in the matter and radiation of the galaxy, gravitational binding energy slightly reduces the effect.

Try to learn a little about the subject before you post this sort of pseudo-scientific disinformation.

The consideration that the energy of gravity is negative would violate the equivalence principle and as such the relativity itself, ..

Nope, it just causes negative curvature. That's the way maths works.

This equivalence is hardwired in Schroedinger equation of quantum mechanics too: only absolute value of Hamiltonian contributes to the amplitude of the probability wave - not the actual value of wave function.

And the Hamiltonian of a closed universe is precisely zero as others have said already. Since matter is positive, the gravitational potential must be equal in magnitude but negative.

As for "AWT", of course there is no such theory.. they were rejected by basic observations - a century ago (!)..

The dense æther model was proposed first with Oliver Lodge in 1904 and it was handled in the same way, like the cold fusion at nickel. As every potentially explosive finding it was never refused with peer-reviwed physics - it was simply ignored in quiet, because every interest about it (even negative one) was undesirable. Therefore AWT cannot be refused, until you link some study which really does so.

lensing is due to the positive energy in the matter and radiation of the galaxy, gravitational binding energy slightly reduces the effect.

A) Radiation of the galaxy isn't "gravitational binding energy" B) it doesn't reduce the gravitational lensing. You're apparently promoting some unknown theory here. The photons withing galaxy indeed do contribute to the gravitational lensing in the same way, like every other form of energy (gluons, W/Z bosons) enclosed there.

Those are all the reasons why scientists have chosen that particular career. Being a scientist is NOT about just using models. It's the interesting/puzzling parts that make it all worthwhile (and so much fun to do).

When a scientist tells you they have found something unexpected/baffling/mysterious then that is an expression of utter joy - not something that would make them feel like they have failed or that there is some problem.

a failed theory can go on in perpetuity

A theory will go on as long as it is useful and the best we have. Replacing it with another one that is much worse is not a step forward.

The idea of a gaseous aether fails the simplest peer review because gas cannot support transverse waves.

Well, exactly. Which is why the dense æther has been proposed with Oliver Lodge. Suprisingly, many ætherists (T.J.J.See) fighted against it - well, and the relativists ignored it all.

Radiation within the galaxy, such as starlight, is a form of energy hence adds to the gravity.

Well, exactly. Therefore the energy of radiation has no opposite sign to gravitational energy.

Nope, standard GR.

If observed, the Nordtvedt effect would violate the strong equivalence principle, i.e. the standard relativity. At any case, if the energy of gravity field should balance other sorts of energy, it should be as strong and easily observable, like these energies. And it wasn't observed, so you're basing your deductions of unobserved phenomena which are violating established theories. If I remember well, such an irresponsible people are called crackpots in contemporary physics...

...(1)In fact, no one should be allowed to place a rating unless they give their username. (2)Requiring an explanation, too, likely will cut down significantly on the number of craven ratings.

@Julianpenrod: (1)They do give their username automatically (or, rather, Phys.org lists it alongside the ranking given.) when anybody scores a remark. I do presume that you know how to access your own ranking page? Just in case you don't, here is how: click on YOUR OWN username next to a comment that you have made, then click on ACTIVITY. Hey presto, as long as you have made no more than a certain amount of comments since the one that you wish to check up on, you will know EXACTLY who has rated you.... (2)Nice thought, but unlikely to happen. Best Regards, DH66

In fact. drel's "explanation" of the graph is wrong. The vertical axis says "Percentage of Settle Galaxies". That means that each line is supposed to represent the percentage of all settle galaxies that fall into each category. drel is "interpreting" it in a patently illegitimate way simply to contradict me. And note that my correct interpretation receives only 1 star out of 5 while drel's invalid one receives 5. .. Requiring an explanation ..

I haven't rated your post but if I did it would be a 1 and here's why:

The standard way to draw any graph is for the independent variable to be on the horizontal axis. This graph groups galaxies by mass and then shows what fraction of each mass group is settled. That means "drel" is correct while you are wrong. You wouldn't get a "1" for being wrong, anyone can make a mistake. You get the "1" for not thinking about what was said and realising your error but instead trying to make it personal and arguing only to try to save face.

The curve for high-mass spirals "knees over", at about 80% settled, after about 5 billion years. Extrapolating the early steep trend forward, 100% would have been settled, after about 6 billion years. Instead, since that ancient epoch (about a billion years before the birth of earth), few massive spirals have settled. Prima facie, 1 in 5 massive spirals was "disrupted" by some process, plausibly mergers & intense interactions with neighboring galaxies; and disrupted spirals have yet to reform?

This is what most can't quite grasp...that indeed matter nucleates from nothing, ..

You seem to be thinking of some empty space solution.

More like a full space solution? Empty space is instead packed extremely densely with diffusive "somethings" that are simply too small to detect directly. Some react among themselves in a self-sustaining feedback system that produce the effects of a sub-atomic particle of our detectable universe. The limit of this reaction speed as it propagates through the dense underlying medium is c. Matter particles are simply propagating reactions of the undetectable "somethings". The properties of the diffusive medium is key to understanding the cosmology model. Empty space, for example, is in fact simply the absence of reacting "somethings." The dense medium remains, however.

According to "Galaxies in the Universe" by Sparke & Gallagher (p.398):

elliptical galaxies formed all of their stars in bursts at an early epoch (z > 3)

before (z=2), nearly no settled spirals existed; only small bright blue star-bursting irregulars about 10K ltyr across

by (z=1), the most luminous (and largest ?) spirals are settled; and all spirals are brighter & bluer than their counterparts at present epoch -- spirals are now redder than they were at (z=1), as star formation has slowed, and enduring red dwarf stars have accumulated

at (z=1), only 10% of spirals are merging

Those data are consistent with those of this article. For example, amongst the largest & most luminous spirals, only about 20% became disrupted by merger events, so that they have yet to disk down by present epoch. And, the "irregular" galaxies of the book, correspond to the "unsettled" galaxies of this article, the latter gradually evolving into the former since z=1

The epoch from ~(8-5) billion years ago corresponds to redshifts z~(1.0-0.5). So, from redshifts of one to a half, the largest and most luminous spirals, containing most of the stars formed to date (smaller spirals were still slowly settling), were puffy, fluffed up, and irregular. Now, spirals may harbor most of the White Dwarf binary systems, precursor to type Ia supernovae (SNIa). And, Prof. Saul Perlmutter observed SNIa, in distant galaxies, out at precisely these redshifts (z>0.5), finding them fainter than expected. Perhaps the host galaxies, out towards redshift 1, were fluffier, puffier, dustier, and irregular, such that some of the SNIa light was scattered out of the sightline to earth ??

Perhaps the host galaxies, out towards redshift 1, were fluffier, puffier, dustier, and irregular, such that some of the SNIa light was scattered out of the sightline to earth ??

The light from Type Ia is not beamed, it is pretty much omni-directional so as much would scatter towards us as away. What a dustier galaxy would do is alter the spectrum to make it redder but without moving spectral lines. That would be measurable.

That seems cogent & clear. But, according to "Extragalactic Astronomy & Cosmology" by Peter Schneider (pg.389), cosmically, at earlier epochs (z>0.7), most star formation [in galaxies] is hidden, in optical bands, by dust. Could such extreme extinction absorb light energy, locally, presumably ultimately into the temperature of dusty gas within the galaxy? The most distant SNIa observed reside at redshifts z>0.7, and so plausibly in dusty (and unsettled) galaxies. SN exploding inside dense clouds & nebulae can be hidden from view, yes? So perhaps something could occur in distant galaxies, too?

The light from Type Ia is ... pretty much omni-directional so as much would scatter towards us as away. What a dustier galaxy would do is alter the spectrum to make it redder but without moving spectral lines. That would be measurable.

Please ponder Quasar "J1148 5251", observed out at redshift (z~6.4). The Quasar's host galaxy is seemingly so shrouded in dust, that no stars are seen. Surely, some (core-collapse) SN are occasionally occurring there; but none may ever be noticeable here. That Quasar's host galaxy resides out at much higher redshift, than galaxies hosting SNIa observed for studies of speculated "Dark Energy". But, in principle, dust may be able to block (or dim) starlight?

According to Wikipedia, Classical Cepheids, dimmed by dust in the disk of their 'Centaurus A' host galaxy, appear to be 3 to 3.5 Mpc away. If so, then dust can dim stellar sources by ~15%. So perhaps dust could dim SNIa also? 'Centaurus A' has an exceptionally dusty disk, compared to cosmically local galaxies; but its dense dusty puffy fluffy disk plausibly resembles the disks of ancient galaxies, observed out at high redshift (z~1), from where important SNIa observations derive. If said SNIa were similarly dimmed by 1 part in 6, then their famous faintness could be accounted for.

Not just in principle, it happens in many cases but the amount of absorption varies with wavelength whereas the dimming due to distance is independent of wavelength. By measuring the variation over several wavelengths, the amount due to dust can be isolated from that due to distance. You're absolutely right, but it is a problem so well known that any study of distant SNe must address that aspect.